I managed to get some time to setup an automated generation of the doxygen docs for kernel subsystems of FreeBSD on my webserver.
Every night/morning (German timezone) the sources will be updated, and the docs get regenerated (this takes some time). Currently this depends upon some patches to the makefile and doxygen config files in tools/kerneldoc/subsys. Everything is generated directly in the place where the webserver will look for to deliver the pages, so if you browse this in the middle of the generation, the content may not be consistent (yet).
Please be nice to the webserver and do not mirror this. You can generate this yourself very easy. Assuming you have the FreeBSD source on a local hard disk, you just need to download the patch from http://www.Leidinger.net/FreeBSD/current-patches/ (if you do not find dox.diff, update your FreeBSD sources and everything will be OK), apply the patch, cd into tools/kerneldoc/subsys and run “make all” (or “make vm” or whatever you are interested in). You need doxygen installed, off course.
If you want to setup something like this yourself, just download the script which is doing all the work, change some variables in the beginning, and create your own local version of the complete docs.